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Introduction to Linux - A Hands on Guide

This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter.
For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. They hope these examples will help you to get a better understanding of the Linux system and that you feel encouraged to try out things on your own.

first off, I'd use a dynamically allocated array. The static array will make your binary bloated like crazy (if an int is defined as 32 bits, you have 128000000 bits allocated by the compiler, meaning 16,000,000 bytes. That's a BIG binary for such small code)

int **i = new int[2000][2000];

or something like that ( I'm somewhat hazy on how to do a multi-dimensional array in C++)

Also, I think that you're trying to addres a memory region that's way to large (think of 2000 * 2000, you get 4000000 byte address. This is more than most systems can address if my math is correct, which it probably isn't as I'm doing this back-of-the-envelope.)

The size of an array does nothing to the size of the executable. However, an array that large is simply too big to be allocated on the stack on most systems. Allocate it dynamically or, probably better, use a container from the C++ standard library that handles the dynamic allocation for you. A std::vector for example.
And btw, don't include iostream.h, include iostream. iostream.h is not part of standard C++.

the problem is that with this code, array[x][y] cannot be properly computed, because int** has insufficient information about array sizes.

What happens under water is that to find the proper memory address of array[x][y], the compiler computes something like

Code:

x*sizeof(array[0]) + y*sizeof(array[0][0])

In order to work as expected, sizeof(array[0]) should equal 1000*sizeof(int), which is 4000. However, since array is of type int**, sizeof(array[0]) equals sizeof (int*), which is 4. Hence the wrong array element will be accessed.

To create a multidimensional array dynamically, you have to first initialize the pointer array, then initialize memory for each pointer in that array. This isn't quite the same as a static multidemensional array because it is not likely to be a contiguous block of memory.

Another option is to just initialize a contiguous block of memory for a single dimension array and index it appropriately. (e.g. index = x + y*width; )